Micturition Flashcards
1
Q
- What makes up the upper urinary tract?
- What makes up the lower urinary tract?
A
- Kidney, Ureters
- Bladder, Urethra
2
Q
- Describe what happens physiologically with a blockage or ureteral outflow
- What is a common presentation?
A
- Blockage in the ureters leads to an increase in hydrostatic pressure and ureteral dilation
- Paroxysmal pain (pain when ureters contract) and hydronephrosis (which puts the pt at increased risk for ARF-acute renal failure)
3
Q
- Where can anatomic constrictions occur?
A
- Ureteropelvic junction
- Testicular/Ovarian artery and vein
- External iliac artery and vein
- Bladder wall
4
Q
- What happens in vesicoureteral reflux?
- What is the patient at increased risk of developing?
A
- Ureteral dilation and urine traveling back up into the ureters
- Increased risk for pyelonephritis
5
Q
- What three openings and muscle make up the trigone?
- Where is it located in respect to the bladder?
A
- Two ureteral openings and internal uretheral sphincter as well as the detrusor m.
- Found on the posterior bladder wall.
6
Q
- The intravesical pressure stretch signals activate sensory nerve fibers. With what two anatomical features does this afferent fiber travel with?
- Where does it travel to?
A
- Pelvic splanchnic nerve and hypogastric plexus
- S2-S4 (Sacral micturition center)
7
Q
- What types of afferent fibers sense bladder fullness? Are they myelinated or unmyelinated?
- What type of afferent fibers sense bladder pain? Are they myelinated or unmyelinated?
A
- Alpha delta-myelinated (bladder fullness)
- C fibers-unmyelinated (bladder pain)
8
Q
- Parasympathetics activate which nerve?
- What spinal levels is this nerve associated with?
- What muscles contract/relax as a result of parasympathetic stimulation?
- What type of receptor?
- What NTX?
A
- Pelvic splanchnic nerve
- S2-S4
- Detrusor muscle contracts and internal uretheral sphincter relaxes
- M3 muscarinic
- ACh
9
Q
- Sympathetics activate which nerve?
- What spinal levels is this nerve associated with?
- What muscles contract/relax as a result?
- What type of receptors are activated?
- What NTX is responsible?
A
- Hypogastric
- L2
- Detrusor muscle relaxation and internal uretheral sphincter contraction (so the opposite of the parasympathetics)
- Urethra-alpha 1; Detrusor M (b2 and b3)
- NE
10
Q
- Somatics activate which nerve?
- What spinal levels is this nerve associated with?
- What muscles contract/relax as a result?
- What receptors are involved?
- NTX?
A
- Pudendal
- S2-S4
- External uretheral sphincter contraction
- nAChR
- ACh
11
Q
- What are the two bladder reflexes and which areas of the body are responsible for each?
A
- Storage/Guarding reflex
- Spinal cord
- Voiding reflex
- Brain
12
Q
- *Describe the storage reflex*
- What activates it?
- What occurs as a result?
A
- Bladder filling activates the storage reflex
- Sends sympathetic and somatic outflow
- Result: Detrusor m. relaxed and external uretheral sphincter is contracted
- Urine is stored
13
Q
- *Describe the voiding reflex*
- What activates it?
- What occurs as a result?
A
- Activated by a full bladder
- Afferents send signals to spinal cord and then the brain
- Stimulation of parasympathetics and inhibition of sympathetic/somatic outflow
- Result: Contraction of the detrusor muscle and relaxation of the external? uretheral sphincter
- Urine is released
14
Q
- What three areas of the brain are responsible for controlling bladder reflexes?
A
- Cortex
- Midbrain: PAG
- Pons: PMC
15
Q
- What is the role of the cerebral cortex in bladder reflexes?
A
- Interprets sensation
- Can partially inhibit micturition reflex